AHA/ASA volunteer expert Carolyn Brockington, MD, offers perspective (via Skype) on ISC 19 abstract WP354. She is a neurologist and Director of the Stroke Center at St. Luke's and Roosevelt Hospitals in New York, New York. 
copyright American Heart Association 

"Hypertension, high blood pressure, number one reason why people have strokes to begin with, right? So now put that in a condition of pregnancy where you have a lot of other things happening in addition to that. So sort of this high blood pressure beating against the wall of the arteries, and, as I said, other hormonal changes likely contribute to this. But we also know that there are risks between or differences in risks, I should say, between the races. So now put an African American woman with a traditional risk factor of high blood pressure in the setting of pregnancy, it appeared that both they had the risk of increased risk of having a stroke not only just during pregnancy, or I should say, a delivery, but also postpartum. So it's not just being concerned about delivery, but also the effects that maybe carry on after the pregnancy. So I think the take-home message is really not that people should be scared, but that this is really information to empower them, and to discuss with their own doctor, if they should get pregnant, what can they do to really decrease the risk. The authors went on to say that this is really a time to be aggressive with the management of blood pressure as well as looking at someone's individual risk factors. Not only blood pressure but other things that might impact upon their developing a stroke. So I think this information is important because it provides a sort of setpoint to have a conversation with the doctor and really do something very specific about reducing someone's risk of stroke."